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Updated: Aug 7, 2026
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Nanomechanics of Drug-target Interactions and Antibacterial Resistance Detection
Published on: October 25, 2013
Vancomycin-binding characteristics in patients with serious infections
1Department of Pediatrics, Eastern Virginia Medical School, Norfolk 23510, USA.
Pharmacotherapy
|November 1, 1996
Summary
Vancomycin protein binding is relatively constant in sick adults, with lower variability than in healthy individuals. Unbound vancomycin concentrations show a gender-dependent association, influenced by globulin levels in men.
Area of Science:
- Pharmacokinetics and Pharmacodynamics
- Clinical Chemistry
- Infectious Diseases
Background:
- Vancomycin is a critical antibiotic for treating serious Gram-positive infections.
- Understanding vancomycin protein binding is essential for optimizing therapeutic efficacy and minimizing toxicity.
- Variability in protein binding can influence drug distribution and exposure.
Purpose of the Study:
- To investigate the extent and variability of vancomycin protein binding in adult patients with serious infections.
- To identify factors influencing vancomycin protein binding, including demographic and clinical variables.
- To compare vancomycin binding in acutely ill patients with findings in healthy populations.
Main Methods:
- Prospective, open-label, cohort study conducted in a general hospital setting.
- Inclusion of 44 adult patients with serious infections.
- Quantification of unbound (Vu) and total (Vtot) vancomycin concentrations using fluorescence polarization immunoassay.
- Statistical modeling to assess associations between variables and unbound vancomycin levels, controlling for total vancomycin.
Main Results:
- The mean fraction of unbound vancomycin was 79.5% (range 53.0-96.3%).
- Total variability in unbound vancomycin was low (8.3%) when controlling for total vancomycin, indicating relatively constant binding in sick adults.
- A significant interaction between gender and globulin concentration affected unbound vancomycin; globulin was negatively associated with unbound vancomycin in men but not in women (p=0.022).
- Age, race, creatinine, albumin, prealbumin, and hemodialysis were not significantly associated with unbound vancomycin levels.
Conclusions:
- Vancomycin protein binding exhibits decreased extent and relatively small variability in acutely ill adults compared to healthy individuals.
- Unbound vancomycin concentration is influenced by gender and globulin protein levels, particularly in men.
- These findings suggest that vancomycin dosing may need consideration for gender-specific factors in certain patient populations.
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